A Chinese noodle vendor in northern Shaanxi province has been detained for 10 days after admitting he added powdered poppy plant — from which opium is made — to his dishes to keep customers coming back, Chinese media has reported.

The owner said that he bought 4 catty (2kg) of the substance for 600 yuan ($98) in August. He said he added it to his food to make it taste better and to improve his business, the Huashangbao paper reported.

The opium-laced noodles came to light after police stopped a vehicle driven by a 26-year-old man and tested him for drugs not long after he had consumed a bowl of the noodles.

The man was detained for 15 days on charges of drug abuse and was not released until family members told police how they had also eaten at the same restaurant and tested positive for the drug.

The paper said the risk of becoming a drug addict from the laced noodles, even if eaten continuously for a long period of time, was unlikely.

It added that lacing food with opium poppy was not uncommon in China, with similar cases in 2010 and 2012.